Toolholder



April 25, 1950 F. H. M CLERNON 2,505,634

4 TOOLHOLDER Filed March 9, 1944 5 Sheets-Sheet 1 F. H. MCCLERNON April 25, 1950 TOOLHOLDER 5 Sheets-Sheet 2 Filed March 9, 1944 April 5, H950 F. H. M cLERNoN 2,595,634

TOOLI-IOLDER Filed Marh 9, 1944 s Sheets-Sheet 4 Patented Apr. 25, 1959 Zdit UNITED STATES PATENT OFFICE 6 Claims.

The present invention relates to lathe turrets and more particularly to improved means for moving and maintaining a tool head or holder in proper position relative to the Work.

An important feature of the invention consists in providing simple, efficient and economical means for successively or intermittently positioning a plurality of cutting or shaping tools in operative alignment with the work, said means including a rotatable and axially movable multiple tool head or holder having associated therewith a releasable locking means for maintaining the head in a fixed position. Operatively associated with the tool head and locking means in a clutch mechanism which normally maintains the tool head in a fixed position relative to the work and which is arranged when rotated in one direction to move the tool head away from the locking means. When the clutch mechanism is moved in an opposite direction it acts to turn the tool head so as to present a new tool to the work, and when the tool head is rotated a predetermined distance the locking means is brought into operation to stop the rotation of the head. The clutch mechanism and its associated parts are then returned to their initial position and the clutch mechanism during this return movement causes the tool head to be moved inwardly relative to the locking means so as to maintain the new tool in proper and fixed alignment with the work.

A further object consists in providing the turret housing with a seat or shoulder portion arranged to receive a revolving head rest member so as to provide a firm base for supporting the tool holder during the drilling or cutting operation.

Another object is to provide means for actuating the clutch mechanism so as to present tools of different types to the Work, without the necessity of removing the tools from the holder, said means being manually operable and arranged to be connected to automatic or semi-automatic instrumentalities for controlling the position of the tool head.

A further object consists in providing a revoluble member which is operatively connected to the clutch actuating means so that upon each revolution of the revoluble member, the tool in alignment with the work is moved away therefrom, and the holder is turned to present a new tool to the work.

Other objects and advantages of the inven tion will become apparent from the following description when taken in conjunction with the accompanying claims and drawings.

In the drawings:

Referring to the drawings in which are shown several preferred embodiments of the invention.

Figure 1 is a side elevation with parts in section of my improved lathe turret mounted on a suitable support,

Figure 2 is a vertical longitudinal sectional view of Figure 1,

Figure 3 is an exploded view showing parts of the turret disassembled,

Figures 4, 5 and 6 are detail sectional views showing the difierent positions of the looking or indexing finger during the operation of the turret,

Figure '7 is a vertical sectional view taken substantially along line 1-1 of Figure 1,

Figure 8 is a sectional view taken substantially along line 88 of Figure 1,

Figures 9, 9a, 10, 10a, 11 and 11a are detail views of the clutch mechanism and its associated parts showing diiferent positions they assume during the operation of the turret,

Figure 12 is a detail view of the modified form of the invention showing the turret and clutch mechanism associated with semi-automatic operating means,

Figure 13 is a sectional view taken substantially along the line i3-l 3 of Figure 12,

Figure 14 is a vertical sectional view of Figure 12,

Figure 15 is a detail view of the revolving drum and diagrammatically shows the path of movement of the operating lever,

Figure 16 is a side view of a lathe showing automatic operating means for actuating the clutch mechanism and its associated parts,

Figure 17 is a plane view of Figure 16,

Figure 18 is an end view of Figure 16, and

Figure 19 is a vertical sectional view of the turret and operating means shown in Figure 16.

The improved lathe turret comprises a turret housing or tool head support H) which has a longitudinally centrally disposed bore ll (Fig. 3) provided at its front or forward end with an enlarged substantially square shaped seat portion 12 of substantial area that terminates in an an-'- nular end portion [3. The housing adjacent the inner end of the bore H is formed with a cutout flat portion I4. Extending from the bottom of the housing is a hollow lug l5 which is internally threaded as at I6 and externally threaded at H. A threaded supporting bolt I8 may be arranged to extend through an opening in the bed l9 of the lathe (Fig. 2) and is threadably connected to the lug I5 so as to firmly secure the housing ill and its associated parts in a fixed position. An internally threaded compensating nut 26 is connected to the external threads 5? and may be actuated by a suitable tool inserted in the openings 23 to take up any amount of play between the bolt l8 and the lug I5 so as to insure the housing being firmly secured to its support.

A shait122 extends' through the'bore ll so to be rotatably mounted in the housing it and. is provided with an enlarged annular shoulder portion or sleeve 23 to which is suitably con-'- nected a revolving head rest member 24 which is'v substantially square so as to fit within and en gage the portion 52 of the housing. Extending outwardly from the member :24 is :a.cylindrica l portion 25 to which the tool head 25 is connected so as to rotate and be movable with theshaft 22. The member 2d and the holder 26 may be formed in .one pi'ece. or. separately; but. both are fixed to th.:.Shd,f.t.ltOTb8 movedtherewith: The seat portion l2 and the member.-24:-may =be of-any desired shape .to provide 'a-:,base::orwfoundationsoi as to iinsureethe .tool" headJbeing properly supportediduring .-the operationof thaturret.. The memberx24 preferablyislocatedclose to the front end of the housing lflpthus provid-: ing greater leverage-at therear end :01 the shaft, and serves to reduce vibration whentheiworr. is brought; in contact: with the tool-1 as welliasa to provide proper balance. A.'. compression spring 2'l surrounds the shaft 22' and is confined between the shoulder :Z3 andtheend .wall; 22' of the hous ing so as to urge the :member24 andholdervzb away from the housing. Onthe .portioni-ofxthe shaft 22 whichextends into the cut' out-portion M of the housing there is mountedssuitable:operating means referred to 'as'a' clutch mechanism which preferably'comprises an engagingzicliitch member til-loosely mounted on 'thershaft'.22 and is formed with one or more fiat projections-1 or teeth 30 and recesses 3& whicltarearrangedto engage and interfit. with complementary formed projections 32 and recesses 33 in areceiving clutch member 34 which is. keyed. vOr -otherwise none rotatably secured to the shaft. The fiat projec-ttions on the clutch'members rare preferablyliseparated from their adjacent recessesxby: inclined portions iiilc' Anadjustingrn ut 35-?is. connected to the reduced threaded end 36 of the shaft and bears .againsti aiwasher' Bl whichflengages-the clutch member '34" so as to maintain the parts of the clutch mechanism in proper operative position. tioned between the end'wall ofthehousingor sup; port iiiand 'the'reeeiving clutch member t tso that the housing constitutes an abutmentf or 11111- iting the axial movement Of-theJengaging .mem her 2% in one direction while the fixedrclutch member 34-limits :the axial'...movement:o. the engaging lllfill'lblxillf an opposite; direction;:..

The housing' i i3 hasxa longitudinal opening I 63 extending therethrough' and preferably'positioned above and-pami1ei= withzxthe ebore at i and .uwhich has a reducedrport: 3tfiwhichmommunicates:with the portionalfi of the housing. Mounted'inrthe opening-3t is a-movable locking orindexing meme be'r- '4fl inxwhichais positioned aepin 4i. thatxis urged outwardly into the portion: 1 2 and "against the adjacent surface of: the member 2 24 by a spring 42. Extending. outwardly 'fromthe. oppoe site end of the member .40 is;an-.integral pin .or projection'tdtwhich israrranged'to .fit into. a groove: 44 in .the adjacent zface of.v the .clutch The. Lengaging clutchifmember: 29 J is posimember 29. A coil spring 45 surrounds the pin 45 and is confined between the wall of the housing and a shoulder on the member 40 so as to coast with the spring 42 for urging the pins 4| and outwardly in opposite directions. The inner surface of the member 24 has one or more spaced openings or holes 46, which as the shaft 22 is rotated, are arranged to be successively ena ed by the pin 4! to prevent further rotation of the shaft 22 and the headzZG. As shown, four openings ii'i'are provided which are spaced 90 apart to allow the shaft 22 to make a quarter turn before being stopped and the number of these openings correspond to the number of difierent types or sizes of tools carried by the head.

The pin ii and its associated parts constitute a releasable stop means for arresting the turning movement of the tool turret 26 when the latter rotates-a predetermined distance, so as to present a new tool to the work.

Inorder to preventdirt and other foreign I matter: fror 1 entering the .front. .end: .Of-.thB-: housing. iijaxclosure plate. .41 is, provided; This-plate may, be composedoi xtwo'sectionsjdfi (FiggB); having a central opening 49 throughuwhich -the shai-t"22 extends. The sectionsr48 are also formed with holes 5i which register. with complementary threaded holes 5! in-the outer faceof the portion i3 and receive the threaded bolts 52 to secure-the plate il to'the. housings The clutch mechanism isenclosed-ina casing 53 whichiis shaped ;to-.con-; form to the curvaturezofithe housing and.is*ar rangedto rest on therendportion l4 andbeisuite ably, securedthereto .so" as I to/prevent foreign matter from. entering-the clutch mechanism. The engaging clutch member. Zitisprovided with suitable manipulatingmeans sucheastheshandle or. lever at which. extends-gthrough a transverseslot 55 in thecasingjt so as tozbe conveniently, mane ually actuated or be connectedto suitable.,-instrumentalities for automatic operation... Theouter end of the casing153 may be provided-withan opening at to permit convenientaccess-tothe nut tbi'when .-it .is I desired for-.anyreason. either. 'to

;-;. adjust the clutchmeohanism or-remove the same.-

Normally; the clutch mechanism. assumes :the position shown dn Figs. 1, 9 and 190.. with the projections or teeth '36- and- 32 .in .engagement and the recesses 34 .iand. t3 spaced irom. each ther. In this-position, the :clutch mechanism acts to compress the spring 2?. andto-maintain the: head rest member. 24 .inengagement:with its correspondingly shaped seat porno-n12 oi the housing, to provideasolid and. firm..foundation for supporting theouter endoithe shaft and the tool holder=.26.. Thepin ,43 on the locking means dii now extends into the recess 44 (Fig.4) on the clutch member .29 while .theopposite end of pin a: fits into theadiacent opening 45 to maintain one oi the tools 511 in proper. alignment with the WOI1.. The projections BG'are of sufficient length .to provide a flat .COIltaCtihgfiillfhCEi which will Qcoact withthe "head rest member 24 to maintainthe tool head and its associated parts securely in position relative to the work; When it. is desired or necessary to present anew 'tool to'the worl the handle 5d first moved clockwise to bring the projections 33 thereof in engage-- ment with theadjacent recesses-331m theiclutch 3% (Figs. 10 anduloah Whenzthisgtakesgplace, the tensionof thepcompression. spring 21 is re. leased sothat theshaft 22 is moved :axially; and the head rest member 84 is moveduawayyirom its seat portionlfi .intoqtheportionLl3 (Fig.2). At the same. time,. the pin '41 .i .--.release'd; from engagement with its adjacent opening 46 (Fig. The clutch engaging member 29 is now locked to the shaft 22 and upon moving the handle 54 in a counter-clockwise direction (Figs. 11 and 11a). shaft 22 together with the member 2t and tool head 26, are rotated a quarter of a revolution. The pin 43, during this movement, passes out of the recess 44 and yieldably engages the flat surface of the clutch 29 (Fig. 6) which forces the locking member inwardly and causes the pin 4! to bear against the adjacent fiat surface of the member 24 until it registers with the next opening 45. When this occurs, the pin is forced into the opening by the compression of the springs 38 and 42 so as to prevent further rotation of the tool head 26 and present a new tool in proper alignment with the work. The handle 54 and clutch mechanism are then returned to their normal or initial position to bring the adjacent fiat teeth in contact with each other and to move the shaft 22 together with the member 24 and tool holder inwardly so that the member 24 firmly rests against the seat portion 52. When the return movement of the clutch mechanism is initiated, the inclined portions ti) on the clutch members ride up the adjacent fixed inclines on the clutch member 34 so as to force the clutch member 34 away from the clutch member 29 and move the supporting member 24 in engagement with its seat portion l2. This movement also compresses the spring 21. The projections 30 are now brought into engagement with the projections 32 so as to maintain the parts in proper operative position. Preferably, the corners of the portion l2 of the housing and the member 24 are cut or rounded as at 58 (Fig. 7) so as to eliminate sharp corners and to facilitate smoothness of action of the member 24 when being moved into and out of engagement with its seat portion l2. The clutch mechanism and its associated parts now assume the position shown in Figs. 1, 9 and 9a and upon repeating this operation the tool head may be moved a quarter turn to present a new tool in proper position relative to the work. The spaced tools 51 are shown connected to the sides of the head by the clamping means 59. However, it will be clear that these tools may be attached to the front of the head in any suitable manner so as to be successively or intermittently presented to the work.

In the modifications shown in Figs. 12, 13, 14 and 15, the parts of the turret lathe are substantially similar in construction and operation to those previously described. However, instead of providing a manually operating handle for moving the clutch mechanism, a manipulating lever 60 is connected to the engaging clutch 29 and has associated with it means for semi-automatically turning the tool head 26 to present a new tool in alignment with the work. In order to efiect this semi-automatic operation, the housing it has secured to opposite sides thereof, the spaced arms 6! and 62 (Fig. 13) by the threaded bolt 63 and the nuts 64. A transverse shaft 65 is journalled in the upper ends of the arms BI and 62 and has secured thereto a drum or revo luble member 66 which is provided with a concave surface 67. The periphery of the surface 6'! is formed with a groove 68 in which extends the head 89 of the lever 60. This groove is so shaped that when the clutch mechanism is in its normal position with the fiat faces of the teeth in engagement and the head rest member 24 moved against its seat l2, the lever 60 will asstune the position as shown in Fig. 13 and be 10- cated substantially centrally of the surface 61. To one end of the shaft 65 is connected a wheel 10 having a knob or handle H which is arranged to rotate the drum 66 so as to provide a semiautomatic operation of the tool holder and its associated parts. The configuration of the groove 68 is such that upon a complete rotation of the drum 6! by the actuation of the wheel 10, the lever 60 is first moved from its neutral position A (Fig. 15), in a clockwise direction through an arc of substantially to the position B (Fig. 15) so as to move the clutch members 30 and 34 from the position shown in Fig. 9a to that disclosed in Fig. 10a so as to release the compression of spring 45 to move the member 24 away from the locking pin 4| during the first quarter turn of the drum 61. The clutch members 29 and 34 are now locked together and as the drum continues to rotate, the lever is returned to its neutral or central position and then proceeds in a counter-clockwise direction through an arc of 45 to the position C (Fig. 15). During this movement, the shaft 22 and tool holder 25 are moved a quarter turn to present a new tool to the work. The drum 66 has now-rotated of a revolution and as it completes a full revolution, the lever 60 is returned to its central position A which causes the actuation of the clutch mechanism to move the member 24 in engagement with its seat l2 so as to support the tool head firmly in position during the operation of the device. Thus, it will be seen that upon each revolution of the drum 6? a new tool is moved to contact with the work. 7

In th modification shown in Figure 16, utomatic means are provided for actuating the clutch mechanism in order to present a new tool to the work. In this form of the invention, the turret lathe i5 is provided with the usual chuck or Work holder is revolubly mounted on an operating shaft H which is connected to any suitable driving mechanism not shown. The tool holder '18 is connected to the shaft 19 revolubly mounted in the housing 80. The housing as is formed with a substantially square portion 8| which constitutes a seat or support for the member 82 on the shaft 19. A spring 83 surrounds the shaft 19 and is confined within the housing so as to urge the member 82 away from and out of engagement with its seat portion 8|. Yieldable stop means 84 is provided with a pin 85 at one end arranged to fit in the spaced openings 85 in the member 82 as the latter is rotated, so as to present a, new tool to the work. The opposite ends of the locking means 84 has a pin or projection 81 which normally-engages in a recess 88 in the clutch engaging member 89 that is loosely mounted on the shaft '59. A receiving clutch 99 is associated with the clutch 89 so as to control the rotation of the tool head 18 and its associated parts in substantially the same manner as shown in the forms of the invention previously described.

An operating lever 35 is connected to the clutch 8S and has a knob or head 92 engaging in a groov 33 of a drum Q4. The drum e a is mounted on a shaft 95 carried by the arms or standards 96 which are secured as at 9? to the sides of the turret. The turret housing 89 and its associated parts are preferably carried on a movable base 98 (Fig. 18) which is slidably mounted on a support 99 and may be moved toward and away from the work chuck it in any suitable manner such as by the screw shaft I00.

. The shaft 95 is connected to a wheel 9E" having teethrei'rin its'isperipherygand a =lug;98.':- extending from? ones-side cthereot. Aestationaryyracke I i! fhavinggteethei 8331s clamped as. at l I13 300 :one side o-the.;lathe-bed 115.: Aefixcd bracket-for armeifi is; also:v secured atoitheelathe-was atvl t= and has its lupper zendizprovideduwithf'a headel ll6-= having arcurvedportionzl illwhich is; arranged to engage the lug sit-ion the wheel-.96: whenithe tool holder isineits cutting or shaping-position:- The teeth 97 on the-wheel 96'.- are'interrupted atglfldsfor a purpose which..willsubsequently ebe described. 2

In-operation; the :tool holder; Ell =r-and -its.associatedparts are maintained in arfixed :position by the:.clumhcrnechanism. and the "member :82 r'so'as toainain'tain one 1of.--:the l-tools.-1l (l 9 carried "by ;the fronts of v' theholder, nrprOperposi-t-iOn. relative to thee-works. When it 11s? desired :or. necessary to present a new tool to the work,- thevscrew 30 I is rotatedzto rmove': theesupport 99' and the-housing as eto move theteeth: 81 1 on; the wheel as: in: en; gagement wit-h the teethrl 62 on theadjacentlend Ofuthe rack tel;- As the turret housing continues itsvmovement .to-:the":opposite-eenduof the rack;

the wheel 19S is-rotated so: asxto makez'a complete revolution and as sitedoes theelever' 92. -on .the clutchdfi ismovedz-to release the member.- 32%110!!! itsseat "and\to:rotate the holder is to -present a new toolain alignment-iwith lthework. The looking .meansrs-t as themember =82-:rotates; is forced intoiengagementwwith anvadiaoent opening; 355 :to prevent further-notation -.ofnithe' head a'l 8 inisub stantially;the-:samermanner as. described in :the previous .forms oi the: invention.v The turret housing Gil and the wheel 96, together withtheir associatedparts, ar --then returned to: the work byisuitable means SUChCaS athecreturn screxv-l l2, and the: luggsli is caused .to "rlderOn :the curved surface 5 it? ofthe arm l G4 to turn the w-l'ieel- $5 in order to .move :thtednteritupted :portion 1! 8% Y to a posit-ionic insure the teeth. 91- being located to engage the rack teethslflz whentheturning ,op eration is repeated; Thee-frictional engagement oitho'olutch members 89 andSll-Which arefir'mly and adjustably mounted.onithe shaft-19 by the nut. l lllract to-;-mai-nta'in.-:thewwheel 9'! and its associated .parts in; a stationary position when the=latter isinot engaged with 'the rack it 1. Thus, automatiomeans areprovided for moving the tool holdera: quarter turn. during. each complete revolutionar the zdrum st and. wheel: 96 so as to present a new tool .to-.'the:-work andmaintain the-*holder-in: proper operative' contact with the WOIk;-.

It-w-ill be seenthat in tallcforms oi theinvention,1th clutch mechanism'isoperatively associated with the'tool head andthe-locking means to-normally maintainthe tool-in a fixed position during the cutting or drillingi operation, and which-allows a-newtooltobe presented to the work-by the simple expedientof either-manually or automatically actuating theclutch mocha-.- Moreovenaoneor more'toolswhich may be required to complete the work can be carried by the holder :without the necessity of removing the tools from the holder; The restmemberiis supg ported by, theehousingjandizis l sitioned close to thetooi-ihead or. frontzpart "of the turret, in order to provide a firm ands-solid foundation "for maintaining-fiche tools iniafixed positiorrwhen in cpera.tion;-and alsoservesto reduce vibration and wear on .the'partaz. Thewclutch mechanismiscon; structed and arrangeditolbe operable either by hand, automatically or 1 semi-automatically; and insures the proper alignmentbf-teachtooltwith the work-at aminimumiexpenditure of time and efiort'i; While therturret-has beenrshown'anddea scribed .as arrangedzto be' moved outwardly away from its .seat, it'will bemanifest that the rotation of the. turret headand the axial movement. of

. the shafti22 maybe reversed so-as initially to be 'illllStl'QitiVBiOf preferred :embodiments; and :that

such changesm'ayb'e made as-fal'l withinzthelpnre view of one skilled Sintthe art 'Without..:departing fromthe spiritoithe inventionand the scope of the claims;

Iclaim:

1.. In a-lathe turret, the combinationrof a lions-1 ing'having a' seat portion, an axially movable shaft revolubly mountedin said housingjand having "afmultiple' tool head. at. oneend :thereof are ranged .lsuccessively to. :present the tools .to :the work, 'springmeans normallyurging the toolhead away from the :housing, a rest member fiXEdiitO the :shaft and "arranged. .to engage said seat,:' releasable stop, means :carriedib the housing;- said 'rest: :member having spacediopenings arrangedxto receive the stop meanswhenmovedin alignment therewitha clutch mechanism including-a clutch engaging'member loosely mounted on theshaft and operatively connected to-the stopmeanaand a receiving clutch member keyed to the shaft, said clutch members havingopposed flat and recessed portions,w theflat portions. being norll ally inengagement' .to maintain. said rest member in contact with said seat, and means for actuatingthe clutch mechanismso that upon the-engaging member being moved in one direction to move the fiat portions in engagement with-the adjacent recess portionsandrelease the spring means to move the .head away from the'housing and-the stop means, said'clutch mechanism when moved in an opposite direction: rotatingztheshait and tool head-,said stop; meanswhen the shaft rotates az predetermined. distance-engaging one of :the openings to- :prevent further. movement of :the shaft, said clutch: -engaging; :member when .the clutch mechanism is-returned-to its normal posi-.

tion actuating theeclutchreceivinggmember and theshaft to move the .tool holder in engagement With said-rest member.

2.-In--:a', machine of. the -.class described, the combinationllol; a afixedssupportr a revoluble-and longitudinally-,rnovable .shaft on said support, a multiplatool headifixedito one end of said shaft, spring. {meansJor-v moving theshait raW-ayiirom ;the';.support; stop;means--.carried hygsaid support and .arrangedto lock theqtoolhead ata :prede.- terminedpointttoprevent rotation thereof soas towmaintain'a new tool. iniallgnmentiwith the Work; yieldable means for-urging; the stop means aivay fromrthe tool head; operatingjym'eans include ing'an. engagingmember loosely. mounted .on: the shaft. and a -receiving member fixedto lithe-shaft, saidengaging member beingwpositioned between the fixed support and thereceiving member; said support-constituting anabutment for limiting the axial movement of the engaging member in one direction and the receiving member limiting the axial movement of the engaging member in an opposite direction, said members having opposed projecting portions and recessed portions, means operatively connecting the engaging member to said stop means for moving the stop means toward the tool head and against the tension of the yieldable means, the rotation of the engaging member to bring the projections thereon in engagement with the projections on the receiving member, moViIlg the shaft and tool head inwardly toward the support to tension the spring means and maintain the tool head in a fixed operative position relative to the work, and the turning of the engaging member to move the projections thereon into the recessed portions on the receiving member, releasing the tension of the spring means so that the latter moves the shaft and tool head away from the support, and means for rotating the engaging member to move the projecting portions and the recessed portions thereon into and out of engagement with the projecting portions and the recessed portions on the receiving member.

3. In a machine of the class described, the combination of a fixed support, a revoluble and longitudinally movable shaft extending through said support, a tool head fixed on one end of said shaft, said tool head having spaced Openings on one side thereof, releasable stop means mounted on the support and arranged to be moved into one of sad openings to arrest rotary movement of the tool head, yieldable means for moving the stop means away from the tool head, spring means associated with said shaft for moving the tool head away from the support, operating means including an engaging member loosely mounted on the shaft and a receiving member fixed to said shaft, said engaging member being positioned between the fixed support and the receiving member, said support constituting an abutment for limiting the axial movement of the engaging member in one direction and the receiving member limiting the axial movement of the engaging member in an opposite direction, said members having opposed projecting portions and recessed portions, means operatively connecting the engaging member to said stop means for moving the stop means toward the tool head and against the tension of the yieldable means, the rotation of the engaging member to bring the projecting portions thereon in enagement on the projection on the receiving member, moving the shaft and tool head inwardly towards the support to tension the spring means and maintain the tool head in a fixed operative position relative to the work, and the turning of the engaging member to move the projections thereon into the recessed portions on the receiving members, releasing the tension of the spring means so that the latter moves the shaft and tool head away from the support, said means operatively connecting the engaging member to the stop means to force the same into one of the openings in the tool head to prevent further turning movement thereof, and means for rotating the engaging member to move the projecting portions and recessed portions thereon into and out of engagement with the projecting portions and recessed portions on the receiving member.

4. In a machine of the class described, the combination of a fixed support, a revoluble and longitudinally movable shaft extending through said support, a tool head fixed to one end of said shaft and having spaced openings in one side thereof,

releasable stop means mounted on the support and extending outwardly therefrom, yieldable means for urging the stop means away from the tool head, said support having a seat for receiving the tool head, spring means on the support for urging the tool head away from said seat, a clutch mechanism on said shaft between the support and the other end of the shaft, said clutch mechanism including an engaging member loosely mounted on the shaft and a receiving member fixed to said shaft, said engaging member being positioned between the fixed support and the receiving member, said support constituting an abutment for limiting the axial movement of the engaging member in one direction and the receiving member limiting the axial movement of the engaging member in an opposite direction, said members having opposed projecting portions and recessed portions, means operativcly connecting the engaging member to said stop means for moving the stop means toward the tool head and against the tension of the yieldable means, the rotation of the engaging member to bring the projections thereon in engagement with the projections on the receiving member moving the shaft and tool head axially in engagement with said seat and acting to tension the spring means and maintain the tool head in a fixed operative position relative to the work, and the turning of the engaging member to move the projections thereon into the recess portions on the receiving member, releasing the tension of the spring means so that the latter moves the tool head away from said seat, and means for rotatin the engaging memher to move the projecting portions and recessed portions thereon into and out of engagement with the projecting portions and recessed portions on the receiving member.

5. In a machine of the class described, the combination of a fixed support, a revoluble and longitudinally movable shaft extending through said support, a tool head fixed to one end of said shaft and having spaced openings in one side thereof, releasable stop means mounted on the support and extending outwardly therefrom, yieldable means for urging the stop means away from the tool head, said support having a seat for receiving the tool head, spring means on the support for urging the tool head away from said seat, a clutch mechanism on said shaft between the support and the other end of the shaft, said clutch mechanism in-- cluding an engaging member loosely mounted on the shaft and a receiving member fixed to said shaft, said engaging member being positioned between the fixed support and the receiving member, said support constitutin an abutment for limiting the axial movement of the engaging member in one direction and the receiving member limiting the axial movement of the engaging member in an opposite direction, said members having opposed projecting portions and recessed portions, means operatively connecting the engagin member to said stop means for moving the stop means toward the tool head and against the tension of the yieldable means, the rotation of the engaging member to bring the projections thereon into engagement with the projections on the receivin member, moving the tool head into engagement with said seat and tensioning the spring means, the turning of the engaging member to move the projections thereon into the recessed portion on the receiving member releasing the tension of the spring means to move the tool head away from said seat, and means for rotating the engaging member, said clutch mechanism normally posi-v esteem tiond to' maintajin 'the -toolf' head nrngagemem with" said seat and upon' rotation in one 'directitm releasing the tensionof-the spring means tomove thtoblh'eetdout (if-engagement with said seat, Said clutch mechanism, whn-Jrbtatd in=an oppositedirection, turning the'to01 head. and forcing the stop means intoone of- 'said openings, said clutch-mechanism, when returned'to its-initial 15ositiongmoving' the head ih-to engagement with said seat. v

6,-Ina machine-of the c'lass desoribed, the combination of a fixdhousingj -a 'revoluble and -longitudinaliy movable shaft moimted in the housing and having 'a multiple tool head fixed thereon, spring 'mea'ns' formd'v ing the shaft to maintain the tool head away' from the 'housingjreleasable stop' means carried by-the-housing and arranged toi'oek the' tool head -at a-predetermined point to prevent rotation of-the tool "head andmaintain a new toolheadinproperaIi'gnmentWith the Work,

ryie'ldable means for urging the stopmeans away om" the tool head,"- a chitch mechanism includg" an' engaging member loosely mounted on the aftand a receiVing'mmber-keyed to said; shaft,

the fixed snpportand--thereceiving member, said support constituting an abutment for limiting theaxiai"mbvihentof the" engaging member in one direction and the receiving member limiting the aXiaimo /feihent-of the enga "member-Fin 1 id engaging member being positionedbetween 1 2 membersj inovifig theishaft andiztool head iin wardly 'towar d the hbus'ing Eandil tensioning :the spring '-means,' the turning of the engaging member' 'toinbve' the projeetionsthereon intoi the reces-seci portion -ori the receiving memb'er; releasing the tension of thef'spring means soithat the'ilatter moves" the tool h'eadaway irom-the housing, saidmeans operativeiy" connectin the engaging member 'to 'the stop" mans Sd that' -When the tObI headreabhes' a predetermined p'oint to arrest-the ineving thereof to b rmg a new tool in alignment with the work, an means for rotating the engaging m'emb'er' to move-theprojectingportions' and recessed p'ortions thereon into and out of engagemeht 'w-i'th theflproje'c-ting portions and recessed pb'rtibns en the receiving member.

FRANCIS MCLERNON.

-REFERENCES' CITED The "following referencesare '-of"reco'rd" in" the file or this patent:

UNITED STATES" PATENTS 'I bREIG'N PATENTS Number Country 7 Date 114,954 Germanyehmemh-Dec. 15, 1900 150 ,205 Great Britain Sept 2, 1920 164,937 Great Britain June 23,1921 

